I seem to react to iodine above certain levels. Iodine is present in shellfish. If a lobster has been swimming in a tank for a few days, I'm fine. Straight out of the ocean, my throat and lips swell up. It's not that bad, but..

I have been warned that it's probably the iodine in my case and iodine is used in dyes for certain medical imaging tests. It's much higher concentration than shellfish. There are alternatives, so it's not a big deal. https://blog.radiology.virginia.edu/medical-contrast/'

BUT, it is important that your H note on every medical form that he has experienced a reaction to shellfish.

I'd get a second opinion. I would call elsewhere and ask for a test for shellfish and any other possible allergens that your husband can think of.

Here's what: your allergist is probably life that this isn't a life-threatening ALLERGY at present, but it certainly sounds like a need-to-be-aware-of-and-live-with *sensitivity.* And as others have mentions, sensitivities/allergies can escalate.

2nd opinion and take this seriously. Minor food allergies can escalate to anaphylaxis with no warning. Track foods in the meantime but do get him in for testing. Also know 3-4 people who later in life have the tickborne allergy to all products from hooved animals: one man in his 70's and it became serious quickly after being turned away for minor allergies. Another teen who had a serious nut reaction after never having one. Please get him food tested with a different allergist!

Yep, allergies. DS ( who is in his 20s) is now allergic to the raw skin of apricots, plums, peaches, nectarines, etc. If the are cooked (like in a marmalade, poached, etc) he's fine. If they are canned or preserved, also ok. Very carefully peeled and washed, usually ok. Otherwise, itchy tongue and teeth (he says) and swollen lips. Doc says it could escalate to more, so now he avoids at all costs. No other issues and nothing when he was younger.

Food allergies are weird. Get your DH to a doc and have him avoid triggers. They can go away or get worse. No sense gambling.

Brazil nuts burn my mouth as I eat them and so I know immediately. I have a few minutes before swelling, vomiting, and diarrhea begin. If I don't get the epi shot within 30 minutes my blood pressure bottoms out. My sister ate Brazil nuts -- which she'd never had a problem with -- and had just enough time to call her DH's name before falling unconscious. Allergic reactions vary.

Find a new allergist.

I feel like this should be easy to test out. Just eat shrimp again and see if there is a reaction. If there is, then he's allergic to shellfish. If there isn't then he isn't and it's something else in the Thai food.

I had this randomly for a few years in my teens and then never again. It was so weird.